Marine boiler



' J. E. BELL.

MARINE BOILER. APPLICATION FILED AUG,16.19!8.

Patented Mar. 9, 1920,

3 SHEETS-SHEET I.

Patenjned Mar. 9, 1920.

3 SHEETS-SHEET 2- EBB 1. E. BELL.

MARI NE BOILER. APPLICATION FILED AUG-16. "19IH.

Patented Mar. 9,1920.

3 SHEETS-SHEET 3- JOHN E- BELL. 10 B wrI W :YQRK

Specification of LettersgPatent.

MARINE noitnn.

Patented Mai-.9, 19 20.

Original application filed March 1, 1918, Serial 110.1219324. Divided and this application filed August 16,

1918. Serial No. 250,119.

To all wfh om e'tma-y concern "Beitlmown that 1, JOHN E. BnLma citizen of the United' 'States', residing-at iBrooklyn, county of Kings, and State of New York, have invented certain new and user11 1 "Improvements in Marine Boilers, of

which the -follo-wing is a *full, clear, and

exact description. i

FOn March 1st, 1918, i1 filed in "the United fling used in connection therewith, and a superheate'r arranged in certain .novel and very efl'ectlve relations wlth the bollertubes.

These features form -the subject -ofthe present application, which, therefore, is a division of that above referred to.

The present improvement pertains more particularly to the marine type of boiler, and in the specification which follows it is described in connection with a special form of such boiler devised by me, but its more general applicability will be obvious from its nature and the objects accomplished by its peculiar disposition therein. These may best be comprehended fro1n a specific description of the improvement, followed by some observations of a general nature with regard *to its functions and purpose.

In the drawlngs hereto annexed Flgure 1 is a View inelevation of oneside-of a-marine "boiler,--With parts of s the casing therefor removed to exhibit the --superheater and itsrelation-to the structure.

Fig. 2 'is a vertical cross-sectional iew of the complete structure and,

"Fig. 8- isa-similar-cross-sectional View but at rightangles to the plane'of Fig. 2.

"For purposes of this caseit is unnecessary to give more than-a general description of 'the boiler as awhol'e, with which ob ect in view-reference may be "had to Fig. 2. 'In this figure the boiler is shown as furnished with a proper setting 1, the walls being built up in any suitable manner, and it is placed over a -fire'box 2, also of the usual character. The boiler proper is composed oftwo continuous box-shaped headers 3 and 4, connected by straight tubes '5, inclined "forward at-an'angle of 18 tothe horizonta'l.

The steam i and water drum 6 is connected by ni-pples 7-withthe front header 3, and-by circulation tubes 8 with the rear header 4,

which surrounds the furnace.

said last named tubes being in two rows, expanded into the drum above and below the with slightly beveled sides, which are closed byconical plugs 9, and drawn bynuts 11, with a force that presses a soft metal seat or gasket, with which these devices are usually furnished, to the shape of the opening and prevent-further advance of the plugs.

Theheader plates 13 and 14 are connected by hollow stay bolts 1-2, and every other tube 5 is omitted from thersecondrow and every other alternate row, as shown in Fig. "2,0 posite the points occupied by the stay bolts. By this uneans each hollow stay bolt is at the center of a cluster of six boiler tubes, and affords a veryeflective and convenient means for' cleaning or dusting the tube, by the introduction of a steam or air lance "15, through said bolts.

The boiler tubes in the several rows are spaced olosetogether so thatthe gas velocity 'is high and little bafiiing is required. It will also be observed that'thestreams of hot gas passing between the tubes o-f the closely spaced rows expand and mix before they impinge-directly upon the tubes in the next succeedlng row, owing to the position of'the widely spaced tubes, while each closely spaced tube is almost directly in the path ofthe gases passing through the spacesbetween them and therwidely spaced tubes below, and time is a -matter of-prime importance and adds greatly to the eflici-ency of the boiler.

' The boiler is supported by lugs sl6 -riveted tothe sides of the headers near the bottom, as shown in Fig. 1. These lugs rest "in cradles .17 carried :by the box-like leasing" 1 8, The boiler proper is surrounded by and -i-ncl0sed in a casing 19 which is secured to and supported by the headers so that the'boile-r and its casing form a-s'ingle rigid structure. The casing is completed by the addition .of two inches of suitable heat insulation '21, and

two inches of firebrickQQ around -the bank of tubes, while that portion of the casing which surroundsthe furnace is lined with three lnchesv of insulation '28 and nine inches At about the center of the bank of tubes 5 an open space is left to permit the installation of a superheater 25, the tubes of which run at right argles to those of the boiler and are so placed as to leave empty spaces in the front and rear of the superheater.

' Under this superheater there is a baflle 26 of travel, in the main, being at right angles right angles to the tubes, so that when the surface of the tubes is composed of Foster to all the tubes.

WVith the remaining structural details this application is not concerned. It may be stated that the casing is provided with the usual and necessary doors for inspecting the superheater or for gaining access to the interior'of the furnace; that any proper means may beused for opening, closing or securing such doors; that provision may be made for burning either coal or oil under the boiler, and that the plan of pipe connections between the boiler tubes, drums'and superheater may be such as is ordinarily employed or as necessity may require. 7

There is apeculiar andmarked advantage secured by the special system of baffling, which is of such a character that the gases arefree to pass overall portions of the heat ing surfaces while at the same time the retarding effect on the .draft is reduced to a minimum. Thebaflling used naturally leads to the location of the superheater in the position shown.- It will'however be observed that on either side of this superheater is a space constituting a secondary combustion chamber in which the gases have a chance to mix before passing over the superheater tubes. This feature is of great importance in a marine boiler where the volume of the furnace is limited. As carbon monoXid gas,

' at higher rates of driving, enters the tube bank, further combustion is prevented unless the gas canstream into a chamber such as is provided for in; this design in both sides of the superheater. In the absence of secondary combustionof this sort, flaming occurs in the uptake and the efliciency of the boiler is reduced.

Furthermore, these open spaces establish they contact with the'superheater tubes with a steep temperature radient. The gases enter the superheater rom two sides and at rings, or corrugated, it will be thoroughly "and effectively swept by such gases.

The peculiar spacing of the boiler tubes shown results in a better distribution of the gases over and under the baffles. The gas flowing out of a wide space and through the narrow spaces between tubes will tend to have a higher velocity at one point than at another. Consequently, from the ordinary considerations of hydro-dynamics the gas pressure must be greatest at the points of highest velocity, and there will therefore be a flow of gas along the tubes in the wider spaces toward points of low pressure which would result in equalizing the velocities through the narrow spaces.

This lateral flow with the system of baffling shown, will distribute the gas over and under the bafiles so that all portions of the boiler surface are more equally swept by the gases, and in the main the flow is transverse to the tubes through the narrow spaces. The arrangement also permits me to maintain the batlie plates, especially if they be in contact with the closely spaced tubes at a temperature that will burning.

having now described my invention what I claim 1s:

1. In a boiler of the kind described, the combination with a bank of tubes separated at an intermediate point in said bank to form a space, of a superheater located in said space and so that secondary combustion chambers or spaces will be left at the forward and rear ends of the superheater and baffling to direct the flow of gases over the tubes of the boiler, through said combustion chambers and the tubes of the superheater.

2. In a boiler of the kind described, the combination with a bank of tubes, divided into two groups with a space between, of a superheater with its tubes running at right angles to the boiler tubes, supported in said space in such manner as to leave combustion chambers or spaces at the forward and rear sides of the same, and bafiiing to direct the flow. of gases through said combustion chambers and over the tubes of the boiler and the superheater transversely.

3. In a boiler ofthe kind described, the combination with a bank of tubes, divided into two groups with a space between them, of a superheater located centrally in said space so as to leave empty spaces at its front and rear, :1 baflle plate under the superheater, a corresponding baflle above the same and over the bank of tubes, and end battles above and below the superheater, for causing the gases to flow in a sinuous path over the tubes and through the empty spaces.

4. In a boiler, the combination with a bank of tubes expanded at their ends into continuous headers, and divided into two groups with a space between, of a superheater located centrally in said space with empty spaces at its front and rear, a ballle protect them from plate directly under the superheater, a corresponding bafile plate above the same and over the bank of tubes, short battles between the boiler tubes immediately above the empty spaces and above the lowermost row of boiler tubes, for causing the hot gases to follow a sinuous path through the empty spaces and through and over the tubes of the boiler and superheater.

5. In a boiler of the kind described, the combination with a bank of boiler tubes, the ends of which are expanded into continuous headers, and divided into two groups with ya space between, of a'superheater located centrally in said space, with empty spaces in front and rear, the tubes of said superheater running at right angles to the boiler tubes, a baffle plate under the superheater, and end battles among the boiler tubes below and above the superheater space, whereby the hot gases are directed over a sinuous path, through the empty spaces and through and over the tubes of the boiler and the superheater.

In testimony whereof I hereunto affix my signature.

JOHN E. BELL. 

